diff --git a/lib/linguist/languages.yml b/lib/linguist/languages.yml
index cdd67186..921c7ed2 100644
--- a/lib/linguist/languages.yml
+++ b/lib/linguist/languages.yml
@@ -3106,6 +3106,7 @@ XML:
   - .dita
   - .ditamap
   - .ditaval
+  - .dll.config
   - .filters
   - .fsproj
   - .glade